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Open access

Theodora Benedek, András Mester, Annabell Benedek, Nora Rat, Diana Opincariu and Monica Chițu

Abstract

The aim of this systematic review was to analyze studies characterizing vulnerable coronary plaques using optical coherence tomography (OCT) and intravascular ultrasound (IVUS), in order to identify the most efficient invasive technique permitting plaque characterization in patients with acute myocardial infarction.

Method: A total number of 432 studies were identified, 420 through database searching and 12 through manual searching. Eight duplicate studies were removed, leaving a total number of 424 studies to be screened. Twenty-six studies only available in Abstract-only form were excluded, resulting in 398 studies checked for eligibility. Eleven studies fulfilled the eligibility criteria and were included in this systematic analysis. Plaque vulnerability was investigated in plaques with thin cap fibroatheroma (TCFA) versus those with thick cap fibroatheroma, in ruptured coronary plaques versus non-ruptured coronary plaques, in culprit versus non-culprit lesions and in lipid-rich versus non-lipid-rich plaques.

Results: A total of 1,568 coronary plaques in 1,225 patients with acute coronary syndromes (ACS) who underwent both IVUS and OCT for analysis of plaque features were included in the final analysis. The review identified the following IVUS-derived features as significantly correlated with plaque vulnerability: plaque burden (p <0.001), remodeling index (p <0.001), external elastic membrane cross-sectional area (p <0.001), and the amount of necrotic core (p <0.001), while OCT-derived features characterizing unstable plaque were TCFA (p <0.001), lipid arch (p <0.001), accumulation of macrophages (p = 0.03), and presence of intracoronary thrombus (p <0.001).

Conclusion: Both IVUS and OCT are invasive imaging techniques able to provide relevant information on the vulnerability of coronary atheromatous plaques, identifying, as they do, various plaque features significantly associated with unstable plaques. Information provided by the two techniques is complementary, and both methods can serve as a useful clinical diagnostic tool, especially in cases of ACS patients undergoing a revascularization procedure.

Open access

A. Tascu and Simona Mihaela Florea

Abstract

Background: There are yet to clarify some aspects regarding the surgical indications and surgical methods that are at choice for treating ACs. The purpose of the study is to contribute to the ongoing debate on the most appropriate treatment.

Materials and methods: We included in the study 44 pediatric patients (aged < 18 years), operated for ACs in the Neurosurgery I Department, of the Emergency Clinical Hospital “Bagdasar- Arseni” in Bucharest, during the period January 2003 to December 2012. The surgical methods were either a craniotomy or cyst shunting. The information regarding these patients was retrospectively assessed based on their clinical and imaging records, and cross checked with the OR protocols. Treatment efficiency was evaluated considering postoperative clinical status, imaging appearance and postoperative complications.

Results: 84.1% of the patients reported postoperative disappearance or reduction of symptoms, while 13.6 had the same complaints as prior surgery. Only one patient experienced worsening of symptoms. Follow-up imaging showed cyst disappearance in 29.5% patients and cyst reduction in 61.4% patients. 9.1% had no change in cyst volume. Craniotomy correlated with a better imaging appearance (p=0.02). There was no correlation between improved clinical status and cyst fluid reduction (p=0.6). 9 patients (20.4%), all with temporal cysts, experienced postoperative complications, and 7 of them (15, 9%) needed surgery. There was no severe or permanent dysfunction in any of the patients. 42.8% of the cyst shunting patients suffered postoperative complications, whereas only 10% of the craniotomy patients did.

Conclusion: Cyst decompression results in significant clinical improvement and it can be performed with little risk for severe complications. Craniotomy seems to be a better surgical treatment option than cystoperitoneal shunt, with a better neuroimaging appearance and a lower complications rate

Open access

Theodora Benedek, Nora Rat, Roxana Hodas, Diana Opincariu, András Mester and Imre Benedek

Abstract

Background: This systematic review seeks to evaluate the role of epicardial adipose tissue (EAT), quantified either by thickness, assessed by transthoracic echocardiography, or by volume, assessed by cardiac computed tomography (CT), in the follow-up of patients with acute coronary syndromes (ACS). Method: One-hundred forty-four articles were screened, from which 56 were reviewed in full-text. From those, 47 studies were excluded for the following reasons: they did not meet the inclusion criteria; they were either reviews or meta-analyses; the study cohorts included only stable coronary artery disease patients; they did not state a clear and concise study design, endpoints, or follow-up. The final draft included nine studies for systematic evaluation. Results: Of the 2,306 patients included in the review, 170 underwent cardiac CT while the remaining 2,136 underwent transthoracic echocardiography for the measurement of EAT. The analysis found that the EAT thickness was significantly associated with major adverse cardiovascular events (MACE) rates during hospitalization (OR: -1.3, 95% CI: 1.05-1.62, p = 0.020) and at three years (HR: 1.524, 95% CI: 1.0-2.2, p = 0.038). The included studies found that EAT was correlated with the following clinical and angiographic risk scores for ACS: GRACE (r = 0.438, p <0.001), TIMI risk score (r = 0.363, p = 0.001), SYNTAX score (r = 0.690, p <0.0001; r = 0.610, p <0.01), and Gensini score (r = 0.438, p = 0.001). There was an inverse correlation between ST-segment resolution of <70% after revascularization and EAT (r = −0.414, p = 0.01), and the myocardial blush grade (r = −0.549, p <0.001). The EF aggregation ranged between 2.65 mm and 4.7 mm within the included studies. Conclusions: EAT, evaluated either by echocardiography or cardiac CT, correlates with the severity of coronary lesions, with the clinical and angiographic risk scores for acute coronary syndromes, with indicators for coronary reperfusion, and with short- and long-term MACE rates. Further studies are required to fully elucidate the role of this extensively studied but still novel cardiovascular biomarker as part of a risk prediction tool.

Open access

Andreea Barcan, Istvan Kovacs, Ciprian Blendea, Marius Orzan and Monica Chitu

Abstract

Introduction: The recent development of large networks dedicated to ST-segment elevation myocardial infarction (STEMI) led to a significant increase in the number of primary percutaneous interventions (p-PCI) parallel with mortality reduction in Acute Coronary Syndrome (ACS). The number of non ST segment elevation myocardial infarction (NSTEMI) is increasing and the highest mortality rates are encountered in patients with cardiogenic shock and/or out of hospital cardiac arrest associated to ACS. The aim of this study was to identify the factors associated with a higher mortality rate in a global population with acute coronary syndromes presented in the emergency department of a county clinical hospital which serves as a regional center for a STEMI network.

Material and method: This is a retrospective study including 684 patients with acute coronary syndrome admitted in the Clinic of Cardiology from the County Clinical Emergency Hospital Tîrgu Mureș in 2014. In all the cases, the factors that correlated with in hospital mortality were identified and analyzed.

Results: The incidence of arterial hypertension was significantly higher in patients admitted with unstable angina (75.0%) and STEMI cases with less than 12 hours onset of symptomatology (68.1%), while impaired renal function correlated with the presence of NSTEMI (66.6%). The presence of a multivessel disease was significantly correlated with cardiogenic shock. The localisation of the culprit lesion in the left anterior descending artery (LAD) significantly correlated with the development of cardiogenic shock, LAD culprit lesions being present in 44.4% of CS cases as compared with 21.7% of noCS cases in STEMI patients. In NSTEMI patients, the localisation of the culprit lesion in the left main artery (LM) significantly correlated with the development of cardiogenic shock, culprit lesions in the left main being present in 47.0% of CS cases as compared with 28.5% of noCS cases in STEMI patients.

Conclusion: Patients presenting with out-of-hospital resuscitated cardiac arrest due to Acute Myocardial Infarction associate higher in-hospital mortality rates. In-hospital mortality seems to be highly correlated with the female gender, STEMI myocardial infarction and the presence of multivascular lesions.

Open access

M. Kuibida and V. Karitāns

Influence of Optical Aberrations of an Eye on Resolution of Dichoptic Images

A human eye suffers from optical distortions or aberrations classified into lower-order aberrations and higher-order aberrations. The influence of higher-order aberrations on the visual perception has been much investigated. In our study, we paid attention to the influence of interocular differences between the degrees of different type aberrations on the ability to resolve dichoptic images. We investigated four types of aberrations - astigmatism, coma, trefoil, and spherical aberration. The lowest threshold was observed for the trefoil aberration, whereas the highest - for spherical aberration. Thus we have concluded that the thresholds of interocular differences between the degrees of higher-order aberrations needed to resolve dichoptic images strongly depend on the symmetry and orientation of the wavefront map and also on the aberrations to which the observer has adapted throughout the life.

Open access

Lachezar Grozdinski, Mario Stankev and Kocho Dimitrovski

Efficacy of the Carotid Endarterectomy in Asymptomatic and Symptomatic Carotid Stenosis and in Patients with Multifocal Atherosclerosis

Aim. The aim of the research was to study the effect of carotid endarterectomy (CEA) at patients with asymptomatic and symptomatic carotid stenosis, also in the patients with multifocal atherosclerosis (MFA): carotid stenosis in patients with peripheral arterial disease (PAD) of the limbs and ischemic heart disease (IHD).

Material and methods. Colour Duplex Doppler was used for screening of carotid pathology in 1104 patients with PAD, IHD, transitory ischemic attacks and an ischemic stroke. The group of 205 patients who had stenosis of a. carotis interna >60%, were divided into three subgroups - patients with asymptomatic carotid stenosis (ACS), patients with symptomatic carotid stenosis (SCS) and patients with multifocal atherosclerosis MFA.

Results. All 205 patients were subjected to CEA, conducted by a patch or shunt, which was successful performed at 201 patients (98%). Significant improvement of hemodynamic of the regional carotid as well as intracranial arteries on the side of the surgery was determined using Colour Duplex and Transcranial Doppler Sonography (TDS). At a second stage, after the successful CEA, a vascular reconstruction was carried out or an aorto-coronary bypass created in the case of patients with MFA.

Conclusion. CEA in the case of patients with asymptomatic and symptomatic carotid stenosis and a concurrent MFA is an efficient curative method of removing the carotid pathology with a minimum percentage of vascular complications.

Open access

Olivera Andrejić, Rada Vučić, Svetlana Apostolović, Milan Pavlović, Dragana Stokanović, Valentina Nikolić, Tatjana Jevtović-Stoimenov and Stefan Momčilović

Summary

The aim of our study was to determine the factors influencing galectin-3 levels in patients with acute coronary syndrome and decreased left ventricular ejection fraction. We collected material from 37 successive patients with acute coronary syndrome and decreased left ventricular ejection fraction, of which 19 patients had atrial fibrillation, and 18 patients who were without atrial fibrillation constituted a control group. Blood samples used for the biochemical measurements were obtained on the third day from acute coronary syndrome. We used Statistical Package for Social Sciences for data analysis. A p-value less than 0.05 was considered to be a measure of statistical significance. Galectin-3 concentration is directly correlated with age and B-type natriuretic peptide level. Also, our results showed an inverse correlation between galectin-3 and total body weight, body mass index, body surface area and creatinine clearance. The following variables were found to be significant predictors of galectin-3 level: decreased left ventricular ejection fraction, total body weight, LDL concentration and body mass index. We identified factors that can predict a decrease in the left ventricular ejection fraction below 45% after acute coronary syndrome: atrial fibrillation increases the risk by almost six times, and urea concentration increases the risk by 1.2 times for each unit. Left ventricular ejection fraction below 45%, TBW, body mass index and LDL level are good predictors of galectin-3 concentration in patients with ACS and decreased left ventricular ejection fraction. Atrial fibrillation could be a predictive marker of decreased left ventricular ejection fraction.

Open access

Vjosa A. Zejnullahu, Valon A. Zejnullahu, Slavica Josifovska, Nikola Vukovik, Kiril Pakovski and Sasho Panov

Abstract

Telomerase Reverse Transcriptase (TERT) is the main catalytic sub-unit of telomerase, a reverse transcriptase enzyme. Telomerase expression is regulated at many levels, with numerous studies suggesting that up-regulation of human TERT gene (hTERT) at transcriptional level results in immortal cell phenotype associated with cancer. The aim of this study is to determine the correlation between hTERT expression and different cervical precursor lesions, as well as with cervical cancer in patients with confirmed Human papillomavirus (HPV) infection.

The study included molecular analyzes on cervical samples from 214 women and matched Papanicolaou (Pap) test results. HPV detection and genotyping was performed by polymerase chain reaction (PCR) and genotyping. Quantitative real-time PCR (qRT-PCR) was performed using TaqMan probes and were calculated relative to the reference gene.

Results showed significantly increased hTERT mRNA expression levels in high-grade and low-grade lesions compared to normal control samples (p<0.01) associated with 6.31 fold higher risk for developing ASC-US and 9.20 for LSIL. Strong correlation between HPV infection and hTERT expression in the high-grade lesions and cervical cancer was also observed. hTERT relative expression values showed 98% specificity and 100 % sensitivity as indicator of cervical lesions particularly for the ACS-H, HSIL and cervical cancer. In conclusion, hTERT expression correlate with the cytological grade of the cervical lesions and HPV infection and has a potential to be used as a diagnostic and prognostic marker.

Open access

Ting Shan Yao, Xiao Feng Zhu, Jin Hee Jung and Yuan Hu Xuan

Abstract

Soluble N-ethyl-maleimide sensitive factor attachment adaptor protein receptor (SNARE) domain-containing proteins were mainly involved in vesicle-associated membrane fusion. Genetic screening has revealed the function of SNARE in different aspects of plant biology. Among them, Synthaxin-22 (SYP22) a Qa-SNARE has been reported to have a pleiotropic function in plant development including regulation of leaf waving, shoot gravitropism and flowering time. In this study, we identified a new role of SYP22 in regulation of brassinosteroid (BR) signaling, especially in the dark. SYP22 interacts with BR receptor, brassinosteroid insensitive 1 (BRI1), and overexpression of SYP22 enhanced a weak BRI1 mutant bri1-5 phenotype. syp22 mutant exhibits short hypocotyl and it is sensitive to exogenously treated BR while slightly insensitive to BR-biosynthesis inhibitor propiconazole (PCZ) in the dark. Expression levels of BR signaling maker genes ACS5, SAUR15 and IAA19 were slightly higher, while BR6OX2, a BR biosynthesis marker gene, was lower in syp22 compared to the wild-type. In addition, syp22 was sensitive to 2,4-D, a synthetic auxin, in the dark. In conclusion, SYP22 is involved in BR- and auxin-mediated hypocotyl growth inhibition in the dark, which might be via interaction with BR and auxin key regulators to alter their internalization in Arabidopsis.

Open access

V. Grekhov, J. Kalnacs, A. Murashov and A. Vilken

Nitrogen Adsorption by Activated Carbon Saturated with Fullerenes

The ability of activated coal (AC) to capture and hold fullerenes is associated with the AC pore structure and considerably differs for different ACs. To reveal the nature of the AC holding capacity, the authors studied adsorption of nitrogen by AC samples at 77K after treatment by C60 fullerene. For measurements, an Autosorb-1 (Quantachrome Instrument Co., Florida, USA) device was employed. Variations in the pore size distribution are evidence for the role of 1.5-2.0 nm pores in the holding of fullerene C60.